One thing I am short on and that is selection of
capable people.
ie; transmission broke;p took to #one but busy;
so NAPA* car care and they fixed the unit to end
of warrantee; told me in some many words get ___
Next took to AAMCO, Las Vegas, Nv worked until
end of warrantee. $4400 in trash...finally took
to #one(Colorado Transmission; Bullhead, City)
and has been running for 4(FOUR) years and pulling strong.
Bullhead City, Ax

Recently I had an issue with the starter on my Blazer when it was routinely 20 degrees outside so I didn't fix it myself.
I took it down and told them it was the starter but they didn't trust that and did their own analysis, and came back with a bad battery cable & bad battery. They said "it had to be charged overnight!". I took a look at their battery test printout and the "bad battery" took a total of 5 amp hours overnight...
I took it to a place more trusted by my work friends and they diagnosed it as a bad starter.
It now has 6 months on the new starter and I've had no problems with the "bad cable" & "bad battery".

I also once took a car to the dealer for service, since it was the middle of winter, miserably cold to work outside, and I needed to have it fixed quickly. They did seemingly replace parts randomly until it started running right. They were very offended when I asked for the removed parts back, since it was not under warranty. In the following year I found that most of the removed parts were good, and used them as spares for the rest of the time that I kept that car. Also, I never went to the dealer for service again. Asode from troubleshooting, I can randomly replace a lot of parts for much less than the dealer charged, thanks to the local parts store.

I wonder how many trips to the dealership it would have taken to find this? My guess is: they would have done the shoot gun replacement until either: they fixed it or you ran out of money. The earlier Jeeps had a similar problem with rough running, the "standard" flow at the dealerships was to replace stuff until it worked. The problem was intermittent and you never knew if it was fixed or just had not failed yet. Someday, maybe, consumers will demand better diagnostics / more robust engine controls until then we are at the mercy of the shops.